fix(user,customer): return 409 on phone duplicate-key races

Map E11000 from the per-collection phone index to friendly conflict
errors and skip redundant GetByPhone when the phone is unchanged.

Not blocking: IAT test DB may need a one-off dedupe for index build;
phone uniqueness is per collection (users vs customers), not global.

internal/user/errors.go

@@ -1,7 +1,37 @@
 package user
 
-import "errors"
+import (
+	"errors"
 
-var (
-	ErrUserNotFound = errors.New("user not found")
+	orm "tm/pkg/mongo"
 )
+
+var ErrUserNotFound = errors.New("user not found")
+
+func mapUserWriteError(err error) error {
+	if err == nil || !orm.IsDuplicateKeyError(err) {
+		return err
+	}
+	switch {
+	case orm.DuplicateKeyMatchesField(err, "phone"):
+		return errors.New("phone number already exists")
+	case orm.DuplicateKeyMatchesField(err, "email"):
+		return errors.New("email already exists")
+	case orm.DuplicateKeyMatchesField(err, "username"):
+		return errors.New("username already exists")
+	default:
+		return err
+	}
+}
+
+func isUserConflictError(err error) bool {
+	if err == nil {
+		return false
+	}
+	switch err.Error() {
+	case "phone number already exists", "email already exists", "username already exists":
+		return true
+	default:
+		return false
+	}
+}

internal/user/handler.go

@@ -170,6 +170,9 @@ func (h *Handler) UpdateProfile(c echo.Context) error {
 
 	user, err := h.service.Update(c.Request().Context(), userID, form)
 	if err != nil {
+		if isUserConflictError(err) {
+			return response.Conflict(c, err.Error())
+		}
 		return response.BadRequest(c, err.Error(), "")
 	}
 
@@ -274,6 +277,9 @@ func (h *Handler) CreateUser(c echo.Context) error {
 	// Call service
 	user, err := h.service.Register(c.Request().Context(), form)
 	if err != nil {
+		if isUserConflictError(err) {
+			return response.Conflict(c, err.Error())
+		}
 		return response.BadRequest(c, err.Error(), "")
 	}
 
@@ -386,6 +392,9 @@ func (h *Handler) UpdateUser(c echo.Context) error {
 	// Call service
 	user, err := h.service.Update(c.Request().Context(), idStr, form)
 	if err != nil {
+		if isUserConflictError(err) {
+			return response.Conflict(c, err.Error())
+		}
 		return response.BadRequest(c, err.Error(), "")
 	}
 

internal/user/service.go

@@ -117,6 +117,9 @@ func (s *userService) Register(ctx context.Context, form *CreateUserForm) (*User
 	// Save to database
 	err = s.repository.Create(ctx, user)
 	if err != nil {
+		if mapped := mapUserWriteError(err); mapped != err {
+			return nil, mapped
+		}
 		s.logger.Error("Failed to register user", map[string]interface{}{
 			"error":    err.Error(),
 			"email":    form.Email,
@@ -191,7 +194,7 @@ func (s *userService) Update(ctx context.Context, id string, form *UpdateUserFor
 		user.Position = form.Position
 	}
 
-	if form.Phone != nil {
+	if form.Phone != nil && (user.Phone == nil || *form.Phone != *user.Phone) {
 		if *form.Phone != "" {
 			existingUser, _ := s.repository.GetByPhone(ctx, *form.Phone)
 			if existingUser != nil && existingUser.ID.Hex() != id {
@@ -208,6 +211,9 @@ func (s *userService) Update(ctx context.Context, id string, form *UpdateUserFor
 	// Update in database
 	err = s.repository.Update(ctx, user)
 	if err != nil {
+		if mapped := mapUserWriteError(err); mapped != err {
+			return nil, mapped
+		}
 		s.logger.Error("Failed to update user", map[string]interface{}{
 			"error":   err.Error(),
 			"user_id": id,
@@ -586,7 +592,7 @@ func (s *userService) UpdateProfile(ctx context.Context, userID string, form *Up
 	if form.Position != nil {
 		user.Position = form.Position
 	}
-	if form.Phone != nil {
+	if form.Phone != nil && (user.Phone == nil || *form.Phone != *user.Phone) {
 		if *form.Phone != "" {
 			existingUser, _ := s.repository.GetByPhone(ctx, *form.Phone)
 			if existingUser != nil && existingUser.ID.Hex() != userID {
@@ -605,6 +611,9 @@ func (s *userService) UpdateProfile(ctx context.Context, userID string, form *Up
 	// Save to database
 	err = s.repository.Update(ctx, user)
 	if err != nil {
+		if mapped := mapUserWriteError(err); mapped != err {
+			return mapped
+		}
 		s.logger.Error("Failed to update user profile", map[string]interface{}{
 			"error":   err.Error(),
 			"user_id": userID,